Adjustable rule



P. ZIKA. ADJUSTABLE RULE.

(No Model.)

PatentedAug. 31.1897.V

vUNITED STATES ATENT FFICE.

'FRANK ZIKA, OF4 CEDAR RAPIDS, IOVA.

ADJUSTABLE RULE.

SPECIFICATION forming part of Letters Patent No. 589,064, dated August 31, 1897.

Application tied May 25,1897. seguire. 638.019. (No model.)

To all whomV tm/ty concern:

Be it known that I, FRANK ZIKA, a citizen of the United States, residing at Cedar Rapids, inthe county of Linn and State of Iowa, have invented certain new and useful Improvements in Adjustable Rules; and I do hereby declare the following to be a full,clear,aud eX- act description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

The object of this invention is to render a folding rule capable of adjustment, so as to serve asa square or try-square at various angles.

The invention is fully described and illustrated hereinafter, reference being had to the accompanying drawings, forming a part of this specification, in which- Figure 1 is a plan view illustrating the joint portion of the rule to which myimprovement is applied. Fig. 2 is a similar view, but with the top plate removed. Fig. 3 is asimilar view showing the rule set at a different angle, the top plate serving as a right-angled try-square for both arms of the rule. Fig. t is a similar view from the opposite side, showing the rule set at an acute angle, the top plate forming the apex thereof. Fig. v5 is a view of the under side of the top plate. Fig. 6 is a view in perspective of the sliding catch which locks the parts in position. Fig. 7 is a transverse section of thecatch and one arm of the rule in the line a; of Fig. 2.

Similar letters'of reference indicate correspending parts.

In the drawings, A and A designate the arms of the rule, which are provided with suitable hinge-plates A2 and A2, respectively, through which passes a suitable pivot-pin A4. The hinge-plates, which should be of metal to secure requisite strength, are made angular instead of 'circular at the joint, so that when the rule is set in varying positions the angles of the two plates coincide and form a complete angle t0 the rule, as illustrated more particularly in Fig. 3, reference being also had to Fig. 4. It will be readily seen that the angles of the hinge-plates as shown in Fig. 4, when set in the same position as that illustrated in Fig. 3, would coincide With the vexternal angle shown in Fig. 3 as they do I with the top plate B. This would of course not be the case if the hinge-plates were made circular externally.

Outside the hinge and on the same pivot-pin is mounted the top plateB, above referred to. This is preferably made in the angular form illustrated, the angles being ninety and fortyfive degrees, respectively. The two longer sides, which are at an angle to each other of forty-ve degrees, serve each, when in the p0- sition shown in Fig. 3, as one side of a trysquare in connection with the corresponding arms of the rule. The adjacent angles are at ninety and forty-five degrees to the longer sides, respectively, and the side opposite the angle formed by the longer sides lies in the same angle to the longer sides, butin reverse order.

In one armof the rule in a suitable dovetail groove is mount-ed a sliding catch-plate C. This has a nib C', by means of which it is moved back and forth by the thumb or iinger, and at one end is provided with a proj ection C2, adapted to engage withnotches A5, A6, A7, and AS, formed in one of the hinge-plates, as clearly illustrated in Fig. 2. The catchplate also has a projection C3, which engages with suitable recesses B', B2, B3, and B4, formed in the top plate B. In order that the top plate may present a smooth and nished appearance externally, these recesses B', B2, B3, and B4 extend only partially through it, as indicated inrFigs. l and 5, respectively.

It is to be understood that the top plate B may turn freely on its pivot and independently of either arm of the rule.

The operation of the device is very simple and will be readily understood. When used as a rule, the arms of the rule are preferably set parallel, this adjustment not being illustrated in the drawings, but the position of the top plate being as shown in Fig. l. To form aright-angled square of the main arms of the rule, they are set in the position shown in Fig. 1, the slide C engaging with the notches A6 and B2, respectively. In the same manner the rule may form a bevel at an angle of forty-five degrees, as shown in Fig. 3, in which case the slide C engages with the notches A7 and B2, respectively. In this case the longer sides of the top plate form one side of the IOO right-angled triangle with each arm of the rule and thus serve as one side each of separate try-squares, as above explained.

When adjusted to the forty-five-degree angie illustrated in Fig. et, the angle is completed by turning the top plate to the position illustrated, in which case the catch-plate engages with the notches A4 and B2, respectively.

The device as thus constructed is thus adapted to a considerable variety of uses and serves the purpose of several tools, as will be readily understood.

Having thus described my invention, what I cla-im as new, and desire to secure by Letters Patent, is

An adjustable rule composed of two main FRANK ZIKA.

Vi tnesscs J. M. Sr. JOHN, J. F. GRoAT. 

